Physiological Acclimation of Taxodium Hybrid 'Zhongshanshan 118' Plants to Short-term Drought Stress and Recovery
Physiological Acclimation of Taxodium Hybrid 'Zhongshanshan 118' Plants to Short-term Drought Stress and Recovery
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紫杉杂交‘中山山118’植株对短期干旱胁迫的生理适应与恢复
DOI：
10.21273/hortsci10997-16
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发表时间：
2016-09-01
期刊：
影响因子：
1.9
通讯作者：
Hua, Jianfeng
中科院分区：
文献类型：
--
作者：
Shi, Qin;Yin, Yunlong;Hua, Jianfeng
以紫杉属杂交品种‘中杉山118’（T.118）为材料，研究了其对进行性干旱胁迫和干旱胁迫对恢复处理（DS-R）的生理适应。对照(C)处理的植株在整个试验期间每天浇水。结果表明，水分亏缺使气孔减少。电导（g(S)）提高了水分利用效率（WUE），因此，DS-R T.118植株的净光合速率（P-n）、蒸腾速率（T-r）和胞间CO2浓度（C-i）也比C植株降低。随着土壤水分有效性的降低，这种减少变得更加显著。相关分析表明，g(S)与土壤含水量、叶片相对含水量（RWC）呈极显著正相关（P < 0.01）。随着胁迫强度的增加，有脯氨酸、丙二醛（MDA）、抗氧化酶积累和膜电解质渗漏的趋势。干旱胁迫诱导第8天叶绿素总含量（Chl(t)）显著下降（P < 0.05），非光化学猝灭（NPQ）显著升高（P < 0.05）。聚类分析区分了T.118植株对水分亏缺的适应。首先，光合作用与散热有关，其次，抗氧化与形态和渗透有关。复水9 d后，各试验参数呈相反趋势，基本恢复到C水平。这些结果表明，T.118植物由于生理适应的高度可塑性，对短期干旱胁迫表现出相当大的耐受性和恢复能力。
The physiological acclimation of Taxodium hybrid 'zhongshanshan 118' (T.118) plants to a progressive drought stress and drought-stressed to recovery treatment (DS-R) was investigated in this study. Plants of control (C) treatment were watered daily throughout the experiment. Results indicated that water deficit reduced stomata! conductance (g(S)) to improve water use efficiency (WUE) and, as a consequence, net photosynthetic rate (P-n), transpiration rate (T-r), and intercellular CO2 concentration (C-i) were also decreased in DS-R T.118 plants compared with C plants. These reductions became more significant with decreasing soil water availability. Correlation analysis showed g(S) was positively correlated (P < 0.01) with the soil water content as well as leaf relative water content (RWC). There was a tendency to accumulate proline, malondialdehyde (MDA), antioxidases, and membrane electrolyte leakage as stress intensity increased. Moreover, drought stress induced significant (P < 0.05) decline in total chlorophyll contents (Chl(t)) and increase of nonphotochemical quenching (NPQ) on day 8 as a photo-protective mechanism. Cluster analysis distinguished the adaption of T.118 plants to water deficit in two ways. First, photosynthesis was related to thermal dissipation, and second antioxidation was related to morphology and osmosis. Furthermore, tested parameters showed a reversed tendency and restored equivalently to C levels after 9 days of rewatering. These findings suggest that T.118 plants demonstrated considerable tolerance to short-term drought stress and recovery due to a high degree of plasticity in physiological acclimation.